Apparatus and method for feeding bulk material to plural supply locations



Nov. 25, 1958- J. w. POWISCHILL ET AL 2,

APPARATUS AND METHOD FOR FEEDING BULK MATERIAL TO PLURAL SUPPLYLOCATIONS 3 Sheets-Sheet 1 Filed Aug. 12, 1955 rlzW L N Nov. 25, 1958 J.w. POWISCHILL ET AL 2,8

APPARATUS AND METHOD FOR FEEDING BULK MATERIAL TO PLURAL SUPPLYLOCATIONS Filed Aug. 12, 1955 3 Sheets-Sheet 2 Nov. 25, 1958 J. w.PowlscHlLL ET AL 2,861,840 APPARATUS AND METHOD FOR FEEDING BULKMATERIAL TO PLURAL SUPPLY LOCATIONS 3 Sheets-Sheet 3 Filed Aug. 12, 1955dam dado Q53 udu wad hmu mud EU mu 66073.79 IiHmu-ard Nhm h w N2 9 NOm2am whim 2,361,849 Patented Nov. 25, 1958 United States Patent OfiiceAPPARATUS AND METHOD FOR FEEDING BULK MATERIAL TO PLURAL SUPPLYLOCATIONS John W. Powischill, Cheltenham, and Edwin W. Hine II andGeorge Robert Howard, Philadelphia, Pa., assignors to Proctor &Schwartz, Inc., Philadelphia, Pa., a corporation of PennsylvaniaApplication August 12, 1955, Serial No. 528,082

7 Claims. (Cl. 302-11) This invention relates to feeding methods andapparratus and is concerned particularly with the problem of provisionof a system for maintaining a reasonably uniform supply of loose, bulk,material at a plurality of .similar locations from which it is dispensedin the performance of industrial operations. It is in the nature of .arefinement and improvement in the system and features :described andclaimed in our copending application, .Serial No. 513,684, filed June 7,1955. As an example -;of a problem solved by the invention, there may becited the creation and maintenance within the feed hoppers of .aplurality of cigarette making machines of a supply of .tobacco which isordinarily dispensed from said hoppers :substantially continuously inthe manufacture of cigazrettes.

The apparatus and method of the invention may be :employed as a solutionto a large number of feed and :supply problems. Since, however, theprimary research on which they are based relates to maintenance ofasupply of tobacco at each of a number of cigarette making machinesarranged in a spaced arrangement, it will be convenient to discuss theinvention primarily in relation to such problems.

In the supplying of tobacco to cigarette making ma- 'chines from theirrespective hoppers, there must obviously be maintained in the hopper ofeach machine a supply of tobacco sufficient to maintain continuedoperation of the machine. It is Well known to persons skilled in this:art, however, that this does not constitute the total sup- ;plyproblem, for it is necessary not only to maintain a .supply in thehopper, but to maintain such supply at a fairly uniform height andamount, which should vary if :at all only within rather narrow limits.This follows from the fact that any substantial variation in tobaccodepth in the hopper will necessarily alfect the density and quantity oftobacco fed to the cigarette making machine. It is accordingly an objectof the invention to provide a :feeding system which will ensuremaintenance of a virztually constant supply of tobacco at the individualhoppers feeding a plurality of cigarette making machines.

In the past, efforts at maintaining such uniformity of :supply haveeither involved visual inspection together with manual replenishment orcontrol in accordance with 'athe judgment of an operator, or they haveinvolved an effort to accomplish the same type of result automatically;i. e., to feed tobacco to the individual hoppers on a demand basis asfeeler or other sensing mechanism indicated the need for replenishment.This type of control is subject to two basic drawbacks. In the firstplace, it :requires a rather complicated mechanical arrangement, :and inthe second place it does not always respond adeiquately to demand,particularly when two or more hoppers differently spaced from theprimary source of supply demand material simultaneously.

In contrast to these systems the present invention provides an apparatusand process by which the supply may be maintained at each hopper quitesimply within closely defined limits, once the basic supply to eachhopper and operation of the individual cigarette machines suppliedthereby has been established,

A primary feature and object of the invention has been to provide asupply apparatus and method satisfying the requirements of the art asdiscussed above.

A further object and feature has been the provision of such an apparatusand method in which the hoppers are arranged in serially spaced relationand are incrementally supplied in an established sequence to provide auniform supply at starting up and during continued operation.

A further object and feature has been that this system continues tooperate, in accordance with the established sequence, through repeatedcycles until sensing elements associated with one or more hoppersindicate that the amount of material in such hoppers exceeds the desiredamount. In continued feeding of material to the hoppers, the feed tosuch particular hoppers is discontinued until their respectiveassociated machines have been operated to utilize material to an extentwhich again requires feed supply. However, during this interruption thefeed to the remaining hoppers is continued in the established sequence.

A more specific object of the invention, as compared to the apparatusand process illustrated and described in our copending application513,684, has been to provide an apparatus and method in which economyand reliability are improved by simplification and improvement upon theapparatus of that application and its principle of operation. To thisend, the delivery of the loose material into the individual hoppers fromthe conveying apparatus which transports it to the delivery locations,is accomplished by deflecting this material laterally into therespective hoppers by the operation of a system of blowers, and theseblowers are timed with the progression of the material to locationsadjacent the respective discharge zones, so that, by operation of eachsuccessive blower for a timed interval following arrival of the leadingend of the material adjacent such location, a desired increment may bedischarged into each hopper.

As a further object and feature of the invention after delivery of anincrement of material to each hopper in the manner discussed above, thematerial remaining along the entire length of the conveying means issimultaneously discharged by again impelling this conveying meansforwardly, while blowing the material laterally from each dischargelocation into its respective hopper simultaneously.

As a further feature and advantage of the invention, the material isdischarged from the leading end of the conveyor into the final dischargehopper by direct deposit, rather than by lateral deflection, and specialcontrol means are provided to prevent lateral deflection in case anadequate supply is already present at any hopper location, and toprevent forward feeding of material upon the conveyor into the finaldischarge hopper, under particular circumstances involving the presencein that hopper of an already adequate supply.

Still further features and advantages of the invention, and the mannerin which they have been attained, will be evident from reading of thefollowing detailed description in the light of the attached drawing, inwhich,

Figure 1 is a plan view of a preferred form of organization of apparatusfor practice of the invention,

Figure 2 is a side elevation of the apparatus of Figure 1,

Figure 3 is a cross-section on the line 3-3 of Figure 1,

Figures 4l0 are diagrammatic views illustrating successive steps in thepractice of the process of the invention, and

Figure 11 is a diagram of the electrical connections and their relationsto the respective cams which control operation of the system.

As illustrated in Figure l of the drawing, the invention is practiced,in the presently preferred form, by feed of the tobacco or other loosebulk material from a supply source by a master feed conveyor 2%} whichmay be a vertical spike apron, to a transverse conveyor 21 which may bea belt operating alternately in opposite directions to deliver tobaccoalternately to conveying means in the form of belts 22 and 23 by whichit is fed into positions from which it is discharged into the respectivesupply locations or hoppers. With a continuing supply of to,- bacco thusbeing discharged upon conveyor 22, the system will operate asillustrated in Figures 4l0 of the drawing, in supply of hoppers ofcigarette making rna chines from this conveyor.

As conveyors 20 and 21 operate to discharge tobacco upon conveyor 22,this conveyor is advanced in the direction of the arrows of Figures 4-9to cause progression of the leading edge of the deposited bed of tobaccopast the locations from which it is discharged to the supply hoppers ofthe individual machines, as illustrated in plan in Figures 540. In theinitial travel of belt 22, it reaches a point opposite the laterallydirected nozzle 30 of blower 24, the nozzle discharge being directedacross the upper or conveying run of conveyor 22 as illustrated inelevation in Figure 4, to blow the leading edge of the advancing bed oftobacco laterally and into a discharge duct 25 from which it isdeposited into the hopper 26 which supplies the. first cigarette makingmachine of the line.

As the tobacco is fed forwardly by conveyors 20, 21 and 22, the leadingedge will be brought into the successive range of blowers 27,28 and 29,which serve to deflect successive increments into ducts 32, 33 and 3dand hoppers 35, 36 and 37, respectively. The operation of the blower 24is timed with advance of the tobacco upon conveyor 22, so that theblower starts up at the time the tobacco reaches the locationillustrated in Figure 5, and is continued in operation for a time whichmay be equal to the time required for a given portion of the conveyorrun to travel from a position opposite blower 24 to a position oppositeblower 27 Thus, as the conveyor run travels forwardly for this distanceafter the blower starts up, the body of tobacco being fed forwardlyduring this interval will be fed to hopper 26.

After the Hopper 26 has received this desired increment, blower 24 willbe stopped, with the result that the leading edge of the deposited bedof tobacco will again advance during continued feed to and by conveyors20, 21 and 22 until this leading edge reaches the position of Figure 6,opposite blower 27. This blower 27 is then started up. to deflect anincrement into duct 32 and hopper 35, after which blower 27 is stoppedand the leading edge allowed to progress forwardly to the position ofFigure 7. In similar manner, each of hoppers 35, 36 and 37 will receivea desired increment of tobacco by operation of its associated blower.for a predetermined time after the leading edge of the tobacco reachesits associated blower, these blowers being operated in the proper timedsequence to efiect this lateral discharge, as illustrated in Figures5-8,

After performance of the discharge operation illustrated in Figure 8,and the stopping of blower 29, the tobacco will continue to be fedforwardly by conveyors 29, 21 and 22 until it reaches the position ofFigure 9 and spills over from the leading end of conveyor 22 intodischarge duct 3% and hopper 39. After this discharge into hopper 39 hascontinued for a time suflicient to discharge into that hopper anincrement similar to that discharged into each of hoppers 26, 35, 36 and37, Phase I of the feeding cycle will be completed, and conveyors 2t),21 and 22 stopped prior to commencement of Phase 11. During this phase,no further tobacco will be fed to conveyor 22, but the body of tobacco 4remaining on conveyor 22 will be discharged into hoppers 5, 36, .7 andWhen the system reaches the condition illustrated in Figure 9 of thedrawing after discharge of tobacco into hopper 39, there will becontained on conveyor 22 a mass of tobacco approximately equal to thetotal of that which has been discharged into the hoppers during Phase I.Furthermore, there will be approximately equal amounts at locations onconveyor 22 rearwardly of blower 24, between blowers 24 and 27, betweenblowers 2'7 and 253, between blowers 28 and 29, and in advance of blower29, respectively, these equal amounts being also equal to the amountdischarged into each individual hopper during Phase I.

To accomplish the feeding operation of Phase II, this tobacco remainingupon conveyor 22 is discharged simultaneously into the respectivehoppers, and this is achieved by again starting conveyor 22 to feed thetobacco, forwardly while simultaneously operating each of blowers 24,27, 28 and 29 as illustrated in Figure 10. During this phase, conveyor21 may be operated in the opposite direction as illustrated in Figure10, for a purpose to be discussed hereinafter.

In addition to the abovediscussed general features of the invention, itincludes features by which the feed of material to any given hopperaccording to the system discussed above foroperation of Phase I or PhaseII of the feeding cycle is interrupted Whenever the supply to theparticular hopper accumulates to the point where such further feed isundesirable. Thus, in performance of the operation illustrated in Figure6, by which tobacco is fed to duct 32 and hopper 35, when hopper 35 hasreceived a quantity of tobacco in excess of its requirements, theoperation of blower 27 will be skipped When the cycle reaches the normalpoint for such operation, with the result that the body of tobacco whichwould be discharged laterally into duct 32 will instead be fed forwardlyinto the position illustrated in Figure 7 during this part of the cycle.Since the timed operation of the blower 28 does not occur until a pointin the cycle of operations later than that at which the blower 27 isstopped, the blower 23 will not be started, in this instance, until theadvancing forward end of the body of tobacco, has reached the positionillustrated in Figure 8. Blower 28 will operate at this time (assumingthat its hopper is not yet sufficiently supplied), but the forward endof the body of tobacco, which normally would have been discharged intoduct 32, being in advance of the positions of both blowers 28 and 29 atthe time blower 29 is started, will continue in its forward movement andbe deposited into duct 38 and hopper 39.

In a similar manner, it any of hoppers 26, 35, 36 or 37 is already fullysupplied when Phase II of the feeding cycle is started, its blower willbe cut out with the result that no tobacco is received. The operation ofthe conveyor 22 is maintained in Phase II for a time sulficient todischarge any tobacco which may remain on the conveyor because ofdiscontinuance of operation of one or more of the blowers, into duct 38and hopper 39.

In order to prevent hopper 39 from becoming overloaded, the movement ofconveyor belt 22 and the entire conveying system comprising conveyors 20and 21 may be interrupted, after completion of the step illustrated inFigure 8, and without feeding any tobacco forwardly from that positionto the position of Figure 9. Thus, in spite of the fact that hopper 39.occasionally receives an increment of tobacco in excess of its normalsupply, by reason of the interruption of one or more of the blowers asdiscussed above, this fact may be compensated by interruption ofconveyor 22 in this manner.

In the foregoing discussion, we have considered the operation ofconveyors 2t), 21 and Zn, in their relation to practice of the inventionin feeding tobacco to the hoppers in the successive phases, as thoughthis involved the entire feeding system. As a matter of fact, in thepreferred practice of the invention, a plurality of lines of cigarettemaking machines may be supplied simultaneously. Thus, as illustrated inFigure 1, after Phase I of the feeding cycle has been completed withrespect to conveyor 22 and its associated blowers and hoppers, conveyor21 will be reversed as indicated by the arrows, and Phase I will beperformed in feeding of tobacco to conveyor 23 and its associatedblowers 42-45 and hoppers 46-50, in exactly the same way as discussedabove with respect to the deflection of tobacco from conveyor 22 to itsassociated hoppers during Phase I of the operation involving conveyor22. By this sequence of steps, Phase II will be accomplished in feedingthe remaining tobacco on conveyor 22 to its associated hoppers at thesame time that Phase I is accomplished with respect to conveyor 23 andits associated hoppers. Thus, the system is operated in alternateperformance by conveyors 22 and 23, and the feeding operation progresseswith respect to both of these conveyors and both phases in alternation,and with only a brief interruption between successive phases.

Suitable side panels 53 and top panels 54 (Fig. 3) are provided alongthe sides and above the respective conveyors 22 and 23, in order tominimize loss of tobacco and prevent turbulence in directing the tobaccointo the desired locations. The side panels adjacent the discharge ducts25, etc., are of course interrupted at the locations of these ducts topermit discharge of the tobacco laterally into the ducts and thecigarette machine hoppers, as illustrated at 55 in Figure 3.

In the preferred practice of the invention, the apparatus iselectrically timed and controlled by the operation of a synchronousmotor 60 (Fig. 11) which drives through its shaft 61 a plurality oftiming cams, and these timing cams control the operation of individualmotors operating the various conveyors and blowers discussed above.These timing cams control the operation of the motor which drives masterfeed conveyor 20 through switch 62 which closes contacts 63 and 6-4 inthe circuit of that motor. They also control the motor driving conveyor21 in the direction of conveyor 22 (we will arbitrarily designate thisthe forward direction) through switch 65 which closes contacts 66 and 67in the circuit of that motor, and similarly close switch 68 controllingcontacts 69 and 70 in the circuit of the motor driving conveyor 21 inreverse at the appropriate point in the cycle of operations. Throughswitches 73 and 76 and contacts 74, 75, 7'7 and 78, they also controlthe timed operation of conveyors 22 and 23 whose motors are controlledthrough circuit connections including the contacts 74 and 75 and thecontacts 77 and 78, respectively. They also control the individualmotors of the blowers 24, 27, 28 and 29 which have been designated as BL1, Bis-2, BL3 and BL-4, respectively, associated with conveyor 22 andblowers 42, 43, 44 and 45 designated as BL6, BL-7, BL8 and ISL-9,associated with conveyor 23, to insure the proper timed operation ofthese blowers in the desired sequence. Through relay-operated switchgroups 79 and 82, they also control the simultaneous operation ofblowers BL-1, BL2, BL-3 and BL-4 in Phase II of the operation withrespect to conveyor 22, and of blowers BL6, BL-7, BL-S and BL9 in PhaseII of the operation with respect to conveyor 23. For the sake ofconvenience of description the machines associated with the hoppersreceiving their tobacco from the conveyor 22 have been designated as A-1through A-5, respectively, and the corresponding machines receivingdischarge from conveyor 23 as 34 through B5, respectively.

While various combinations of timing features may be adopted within theprinciples of the invention, it will be convenient for us to discuss itin relation to an operation in which, in one revolution of the shaft ofthe synchronous motor 60 operating the timing cams, Phase I of thefeeding operation is performed in delivery of tobacco through conveyor22 to its respective hoppers, and then Phase I is-similarly performedthrough conveyor 23 to its hoppets, while Phase II is being performedwith respect to conveyor 22. During subsequent operation, Phase 1 willthen be performed through conveyor 22 during the first 180 of rotationwhile Phase II is performed through conveyor 23, and during thesubsequent 180 of rotation Phase II will be performed through conveyor22 while Phase I is being performed through conveyor 23. The manner inwhich these results are obtained, and also the manner in which thedetailed control features discussed above are obtained, will be. evidentfrom consideration of Figure 11 in the light of the followingdiscussion.

In starting the system into automatic operation for practice of Phase Ithrough conveyor 22, the portion of conveyor 21 between its transversecenter line and conveyor 23 may first be supplied with tobacco by meansindependent of the control system now to be described, and we willassume that this is the condition at the start of the automaticoperation. We will also assume that the motors driving conveyors 21, 22and 23 are timed to produce conveying movements of these conveyorsbetween the transverse center of conveyor 21 and its respective ends,between the receiving ends of conveyors 22 and 23 and their blowers 24and 42, and between successive blowers, each of which conveying movementoccurs dur ing 15 of rotation of shaft 61 which drives the timing cams.

Referring to Figure 11 of the drawing, the automatic operation isstarted by closing start switch100, safe run switch 101 and thesynchronous motor SMS switch 102. The closing of switch establishes acircuit from line 103, which we will regard as the supply line, toreturn line 104 through line 105, stop switch 106, line 107, UV relay108 and lines 110 and 111, and the resulting energization of relay 108closes the switch contacts which it controls. We will refer to theuppermost of these as UV-l, the next lower as UV-2 and the lowest asUV-3, and employ this same system of nomenclature in referring to theother relay-controlled switch contacts of the system. Since contactsUV-3 are in circuit with switch 102, current will now flow from supplyline 103 through switch 100, line 105, switch UV-3, switch 102 andsynchronous motor 60, thereby starting the rotation of the cam shaft 61.The first effect of rotation of shaft 61 from the 0 starting pointillustrated will be to close switches 114 and 115 by the rotation ofSAFC cam 116 and SOC cam 117, respectively. Switch 115 is in circuitwith line 104 through line 118 and with line 103 through line 119, SORrelay 122, line 123, contacts UV-2, line 107, and switches 106 and 100and line 105 to supply line. 103. Relay contacts SOR-1 and SOR2 willaccordingly be closed by the closing of switch 115.

Each of the switches controlled by the cams on shaft 61 except theswitches controlled by the SOC, CA5 and CB10 cams is electricallyinterconnected through lines 124 and 125, contacts UV-1 and line 126with supply line 103, and the closing of switch 114 accordinglyestablishes a circuit through these connections and through line 127,SAFR relay 128, line 129 contacts SOR1 and line 111 to return line 104,energizing relay SAFR and closing switch 65 to start the movement ofconveyor 21. After 15 of rotation of shaft 61, the leading end of thisbed of tobacco will have been moved from its position at the transversecenter of conveyor 21 to position in which it is ready to be receivedupon conveyor 22. At this point, the timing controls operate to startthe forward movement of conveyor 22 and the master feed conveyor 20, toestablish a continuing supply of tobacco upon conveyor 21 as itcontinues to move forwardly, and to convey tobacco discharged from itsforward end in a continuing stream or bed forwardly on conveyor 22.

Upon completion of 15 of rotation of shaft 61, TFC cam 132 and CAC cam133 operate to close switches 134 and 135. A circuit is thus establishedthrough switch 134, line 136, contacts SOR-2, line 137, switch 101, TFRrelay 138, line 130, contacts SOR-1 and line 111 to return line 104, andthrough switch 135 through line 142,

7 CAR relay 143, lines 144 and 129, contacts SOR1 and line 111 to thereturn line. Relays TFR and CAR will thus be energized simultaneouslytostart the forward movements of conveyors and 22, by closing of therespective switches 62 and 73 controlling their driving motors.

After 15 of further rotation of shaft 61, the forward end of theadvancing bed of tobacco will be in line with the nozzle of blower 24,as illustrated in elevation in Figure 4 and in plan in Figure 5. Blower24 is now started and continued in operation during the next 15 ofrotation, i. e., until shaft 61 has rotated from its initial position.The circuit through which this blowing operation is established iscontrolled by cam CA-l 145 in closing its associated. switch146. Thisestablishes a circuit through lines 147 and 148, switches SO1 149 andLS-l 152, the motor of blower BL1, which is the blower 24 of Figuresl-lO, lines153, 144 and 129 contacts SOR1 and line 111 to return line104. Blower 24 will therefore be operated as long as cam 145 retainsswitch 146 in closed position, except under the abnormal conditionsdiscussed below for preventing this blower from operating when itsassociated hopper 26 already has a full supply of tobacco. Thus, in thenormal course of events, the switch 146 will retain blower 24 inoperation during 15 of rotation of shaft 61 and all of the tobacco fedforwardly at the advancing end of the bed upon conveyor 22 will bedeflected into hopper 26 during this operation of the blower.

After the operation of blower 24 has stopped by reason of the fact thatcam 145 opens its switch contact 146, the shaft61 will continue torotate forwardly for 15 during continued forward movement of conveyors20, 21 and 22. At the end of this time, shaft 61 will be at itsposition, and switch l54will be closed by rotation of cam 155 into itsswitch-closing position. This will establish a circuit through lines 156and 157, switches SO-2 158 and LS?. 159, blower. BL-Z 27 and line 153 tothe return connections discussed above forthe circuit through blower BL124. Cam CA2 will open its switch contact 154 after 15 of furtherrotation, i. e., at the position of shaft 61, thereby stopping blower 27and the deflection of tobacco into hopper 32.

The leading end of the bed of tobacco on conveyor 22 will next moveforwardly to the position of Figure 7, and blowers 28 and 29 will beoperated in sequence, with a 15 interval between operations, by switches162 and 163 controlled by earns 164- and 165, respectively, for closureduring 15 of rotation of shaft 61, with intervals of time correspondingto 15 of rotation between the opening of each of these switches and theclosing of the next succeeding switch, to permit the material toprogress forwardly upon conveyor 22 between successive blowingoperations.

After completion of the feed of equal increments of tobacco to therespective hoppers 26, 35, 36 and 37 as discussed above, and thestopping of the operation of blower 29, the tobacco will move forwardlywithout operation of any blower during 15 of further rotation of shaft61, and it will then begin to spill over into discharge duct 38 andhopper 39 and continue to be fed to hopper 39 in this way during 15 offurther rotation of shaft 61. At this time, shaft 61 will be at its 165point, and the entire feeding system is now stopped, since Phase I hasbeen completed.

From the discussion of SOC earn 117, it was seen that, by the operationof this cam the switch is closed and that this switch controls, throughline 119 and relay 122, contacts SOR1 and SOR-2. It has also been seenthat contact SOR-ll is a part of the return circuit for the relays 138and 128 controlling the forward feed of all con-- veyors 20, 21 and 22.The normal effect of cam SOC 117 in opening switch 115 after of rotationof shaft 61 would accordingly be to stop the forward movement of theseconveyors with the bed of tobacco at the position an interruption of thefeeding operation is prevented, in.

normal operation of the system, by the fact that cam CA-S 166 closes itsassociated switch 167, thereby establishing a parallel circuit throughSOR relay 122. This parallel circuit includes normally closed switchesLS-S 168 and SO-S 169, whose function will be explained hereinafter.

Fromthe foregoing, it will be seen that in the normal operation of PhaseI, SOR relay 122 will remain energized and its associated switchcontacts closed during the first 135 of rotation of shaft 61 by closureof switch 115' by SOC cam 117, and that this condition will continueduring 30 of additional rotation of shaft 61, through closure of switch167 by CA5 cam 166. To accomplish this continued energization of the SORrelay and the conveyor feed, the cams are designed so that switch 167 isclosed before switch 115 is opened. Cam 117 may, forexample, allowswitch 115 to open when shaft 61reaches the 135 point, while cam CA-Sretains switch 167 closed from 134 to switch 115 again at There is atime interval of 30 of rotation of timing shaft 61 between the end ofPhase I and the beginning of Phase II and the beginning of Phase 11during which conveyors 20 and 22 are idle, since cam switches 134.and135 are allowed to open by their cams TFC and CAC during this time. 135are again closed by their cams TFC 132 and CAC 133, for the feeding ofconveyor 20 forwardly in the performance of Phase I of the process tomachines B-l to B5 through conveyor 23' and thefeeding of conveyor 22forwardlythrough 150 in performance of Phase II to .machines A-1 to-A5.Conveyor 21 is started in reverse when shaft 61 reaches 180; i. e., 15in advance of the starting of conveyors 20 and 23, in order to move thebed of tobacco previously deposited and lying between its center andconveyor 22, toward conveyor 22. until it begins to spill over ontoconveyor 23.

In the completion of the feeding steps of Phase II, from conveyor 22 tothe A group of machines, the blowers BL14 are started up simultaneouslywith conveyor 22.

at 195. This is achieved through closure of switch 182 by CAA cam 183completing a circuit through line 181, CAAR relay 184 and theconnections through line 144 to return line 104. Energization of relay184 closes switch group 79, and the parallel blower circuits controlledthereby. Simultaneously with the closing of switch 182 by CAA cam 183,switch 185 is closed by CAAC cam 186, thereby completing parallelcircuits through contacts CAAR 1, 2, 3 and 4, lines 187, 188, 189 and190 and the motors operating blowers 24, 27, 28 and 29, and causing thetobacco to be simultaneously blown into the supply hoppers 26, 35, 36and 37 as illustrated in Figure 10, as it is fed forwardly.

Cams SARC, CB, CB-1, CB2, CB3, CB-4, CBC, CBBC and CB-IO perform exactlythe same functions in control of relays SARR 191 and CBR 193, blowerBL-6 42, blower BL'7 43, blower BL-S 44, blower BL-9 45, thesimultaneous operation ofblowers BL69 in Phase II through energizationof CBBR relay 194, and the maintenance of closed circuit through switch195 after cam SOC again allows switch 115 to open at 315 in feed to theB group of machines, as do the corresponding cams SAFC, CAC, CA-1, CA-Z,CA-3, CA-4, CAA, CAAC and CA5 which control the conveyors and blowersassociated with the feed to the A group. The only difference in thesecontrols lies in the fact that the cams controlling the B groupoperations are timed to perform their corresponding functions exactly180 after the corre-- sponding functions of group A. Thus, the wiringconalternation in the two groups during successive 180" intervals ofeach 360 of shaft rotation.

Cam SOC will operate to close After this interval, switches 134 and Eachof the parallel circuits through the blower motors includes a switchresponsive to the level of material in the hopper into which material isblown by that blower, these being designated LS-l, LS-2, etc. These arenormally closed, and when all of them are in that condition, and thecorresponding switches SO-l etc. are also closed, the apparatus willperform its complete operating cycle in delivering increments of tobaccosequentially into each hopper. When the tobacco has accumulated to amaximum desired level in a hopper associated with any blower, however,its LS switch will open, thus disabling that blower at the time it wouldnormally operate. Thus, if LS-l switch 152 is opened by the level oftobacco in hopper 26 during Phase I at the time switch 146 is closed tooperate BL-l blower 24, such operation will be pre vented, and the bodyof tobacco which would normally be deposited in hopper 25 will bedeposited instead in hopper 39, and the same comment applies to any ofhoppers 35-37 that may be skipped in this manner. If any of the blowersis similarly disabled 'in Phase II, the increment of tobacco which wouldnormally be received in the associated hopper will be received by thenext hopper down the line which requires any tobacco, and with which itsassociated blower is accordingly functioning.

If one of the machines should be shut down for repairs or other reason,it will ordinarily be desirable to discontinue feed to its associatedhopper, and this may be done by manually opening its respective SO 1-9switch such as SO-l switch 149 in the line of blower BL-l. The effect ofthis will be the same as that discussed above for opening of thecorresponding LS switch.

It is desirable that the feed to hoppers 39 and 50 be interrupted attimes, both because of the fact that these might otherwise beoversupplied in normal course of operation, and because of the fact thatthey receive somewhat of an oversupply because of occasionalinterruption of one or more of the blowers through the LS and SO switchcontrols discussed above. In order to correct this, there are providedin the branch circuit controlled by switch 167 and CA-S cam 166, a limitswitch LS-5 168 and a shut-off switch SO5 169, and there arecorrespondingly provided, in the circuit controlled by the switch 195and cam 196, a limit switch LS- 197 and shut-off switch 80-10 198. Theseswitches are identical in their functioning to the LS and SO switchesassociated with the blowers, the limit switches being in every caseassociated with the corresponding hoppers to effect their controlfunctions in case of an oversupply, and the shutoff switches beingavailable to the operator to disable the feeding function in case themachine is shut down. The functions of switches 168 .and 197 inpreventing an oversupply are, however, to disable the feeding system atthe point when the leading end of the tobacco being fed would ordinarilyproceed from the position of Figure 8 to the position of Figure 9. Thus,if switches in the circuits controlled by the cam-controlled switches167 and 195 are open, feed cannot occur to either of hoppers 39 or 50 asthe final step in performance of the operations of Phases I and II asdiscussed above. Cam SOC allows its associated switch 115 to open from135 to 180 and from 315 to 360, but relay SOR is normally maintainedenergized between 135 and 165 and between 315 and 345 by the closure ofswitches 167 and 195 by their cams 166 and 196 for 31 intervalsbeginning at 134 and 314. Thus, when these branch circuits are opened byopening of switch 168 or 169 and switch 197 or 198, the feedingoperations will be interrupted without feeding any tobacco through thelast 30 of movement of conveyor 22 or 23, in either Phase I or Phase II.While an occasional increment of feed will be received by these hopperseven when these switches are open, as will be evident from an analysisof the system, the controls may be applied to prevent the end hoppersfrom becoming oversupplied. If it should be desired to prevent anytobacco whatever from reaching these hop- 10 pers, special conveyor orcontrol features may be ap plied to cause recirculation to the supplysource of to-' bacco which would otherwise be received at undesiredtimes, or other special control or conveyor features may be adopted.

While the invention has been described above in relation to a preferredembodiment of the invention by way of example, persons skilled in theart will be aware that it may be modified or refined in various wayswithout departing from its basic principles. We therefore wish to haveit understood that this invention is not to be limited in interpretationexcept by the scope of the following claims.

We claim:

1. In apparatus for feeding bulk material to a plurality of seriallyarranged spaced locations, the combination comprising conveying meanshaving conveyor run portions movable through successive positions lyingin feeding relationship to each of said locations, means for supplyingmaterial to said conveying means, blowers mounted laterally and abovesaid conveying means and positioned above said respective locations toblow material from said conveying means into said locations, means foroperating each of said blOWers through a predetermined time intervalduring advance of a body of said material forwardly upon said conveyingmeans progressively into the range of each blower, timing means forcontrolling the performance of said supplying, material advancing andblowing steps in regularly timed repetitive cycles, and means associatedwith said supply locations and individually responsive to predeterminedaccumulation of material at said locations for interrupting theoperations of said blowers at locations at which said material hasaccumulated to said predetermined extent, while continuing the operationof the remaining blowers during the continued regularly timed repetitiveperformance of remaining steps of the cycle.

2. An apparatus as defined claim 1 in which said timing means includesmeans for establishing a continuous supply of material on said conveyingmeans opposite and rearwardly from each of said supply locations, andoperating said blowers simultaneously during subsequent forward movementof said conveying means to carry the supply extending rearwardly fromthe respective blowers into the range thereof.

3. An apparatus as defined in claim 1, in which said timing meansincludes means for causing said conveying means to move forwardly with acontinuous bed of material deposited thereon, and means for causing eachof said blowers to operate through a predetermined time intervalimmediately following advance of the forward end of said bed of materialwithin the range thereof.

4. An apparatus as defined in claim 3, in which said timing meansincludes further means operable, following delivery of a predeterminedincrement of material to each of said locations as therein defined,while further material is accumulated on said conveying means rear-Wardly of said locations, to cause said conveying means to moveforwardly during a further predetermined time interval duringsimultaneous operation of all of said blowers to deposit a furtherincrement of material at each of said locations.

5. In apparatus for feeding bulk material to a plurality of groups ofserially arranged spaced locations, the combination comprising means tofeed material to the locations of one of said groups comprisingconveying means having conveyor run portions movable through successivepositions lying in feeding relationship to each of said locations, meansfor supplying material to said conveying means, blowers mountedlaterally and above said conveying means'and positioned above saidrespective locations to blow material from said conveying means intosaid locations, means for operating each of said blowers through apredetermined time interval during advance of a body of said materialforwardly upon said conveying means progressively into the range of Ieach blower, timing means, for controlling, the performance ofpredetermined accumulation of materialat said locations forinterruptingthe operations of said-blowers at locations at whichsaidmaterial has accumulated to said prede termined extent, whilecontinuing the operation of the remaining-blowers during the continuedregularly timed repetitive performance of remaining steps of the cycle.

6.,Inapparatus for feeding bulk materialto a plurality of seriallyarranged spaced locations, the combination comprising conveying meanshaving conveyor run portions movable. through successive: positionslying in feeding relationship to each of said'locations, means forsupplying material to said conveying,- means, blowers mounted laterallyand above saidconveying means and positionedabove saidrespectivelocations to blow material from said conveying means into saidlocations, means for operating each-of said blowers through avpredetermined time interval during advance of a body of said materialforwardly upon said conveying means progressively into the range of eachblower, timing means for controlling the performanceof said supplying;material advancing and blowing. steps inregularly timed repetitivecycles, and

me'ans'associated'with said supply locations and individually responsiveto predetermined accumulation of material atsaidlocations forinterrupting the operations of said blowers-at locations at which saidmaterial has accumulated to said'predeterm'ined extent, While continuingthe operationofthe remaining blowers duringthe continuedregularlytimed-repetitive performance of remaining. steps of the cycle,said conveying means includinga conveyor runv portion having itsdelivery end overlying a further supply location to deposit-incrementsof material therein bygravityin-time sequential relation to the depositthere-' References Cited'inthe file of thistpatent UNITED STATES PATENTS418,042 Mitchell Dec. 24, 1889 2,140,128 Craggs Dec. 13, 1938 2,195,407Craggs Apr. 2,1940 2,537,uu5 Brown et al. Jan. 9, 1951

